function goUrl(x){
var e = event || window.event;
window.location.href=x;
}
window.onbeforeunload=function(){
alert(‘before‘);
}
<a href="javascript:void(0);" onclick="goUrl(‘http://www.sina.com‘);return false;">跳转3</a>
原文：http://www.cnblogs.com/illegal/p/6374288.html